725
FXUS65 KBYZ 300121
AFDBYZ

Area Forecast Discussion
National Weather Service Billings MT
621 PM MST Sat Nov 29 2025

.KEY MESSAGES...

- Colder than normal temperatures through Monday morning; highs in
  the teens and 20s Sunday; lows in the single digits above to
  teens below zero regionwide tonight.

- Increased winds along the western foothills Monday night and
  Tuesday; localized blowing snow possible.

- Another system may bring rain and snow showers, Tuesday into
  Wednesday (moderate chance) with some snow accumulations.

&&

.UPDATE...
Water vapor imagery shows a dry northerly flow over the region,
with a weak shortwave dropping thru the Pac NW toward the great
basin. In fact, we are already starting to see some high clouds
eke into our far west as of 01z. We could see a few light snow
showers/flurries over the Beartooth-Absarokas later tonight into
early Sunday, but otherwise our cwa will remain dry. An area of
stratus remains over Fallon County. As surface winds turn
easterly, some broken stratus seems likely to persist near the
Dakotas stateline for much (if not all) of the night. West of the
stratus, high res models continue to show a risk of valley fog
over mainly the east half of our forecast area. Something to
watch. The other thing to monitor is temperature. A 1037mb surface
high exists over northeast MT and where it is clear, temps are
already plummeting. 6pm temps are -1F at Miles City, and -2F at
Brandenberg and along the Bighorn River just north of Hardin. It
is a chilly -10F just to our north in Jordan. All valleys in
southeast MT will fall below zero tonight...the coldest night yet
of the fall. The west will stay slightly moderated as cloud cover
slowly increases. JKL

&&

.DISCUSSION...

Through Friday...

Temperatures ranged from the single digits to 20s over the area
this afternoon, coldest over the northeast. Heading into tonight,
a 1040mb surface high will gradually slide east through the area,
with temperatures dropping into the single digits above zero to
the single digits below zero. Some locations over the north and
east could drop into the teens below zero. One thing to watch is
the potential for fog/low cloud development over the east, which
could prevent temperatures from dropping as low as forecast. A
shortwave dropping through Idaho into Wyoming will bring some low
chances (less than 25%) for snow showers over the southwest
mountains tonight into tomorrow morning, though any accumulations
will be light. Below normal temperatures continue for Sunday with
highs in the teens to 20s for most areas, warmest over the west.

As heights build in from the west on Monday, a klondike chinook
looks to take shape bringing breezy winds to the west, along with
temperatures back into the 30s for many areas. Winds look to
increase further Monday night into Tuesday for the gap areas, with
the latest probability of wind gusts exceeding 50 mph for
Livingston and Nye around 65%. Will need to monitor the potential
for blowing snow over the western foothills. If temperatures warm
into the upper 30s as forecast, this would limit the potential.

An upper trough is progged to drop south and east from the Pac NW
into the Northern Rockies on Tuesday, splitting as it moves toward
the area. The northern energy looks to drop through the area,
while the southern energy dives into the Great Basin. As it
stands, there is a moderate to high chance (40-80% chance) for
rain/snow showers to move through the area starting Tuesday
afternoon, continuing into Wednesday. While precipitation could be
a rain/snow mix for the lower elevations, accumulating snow is
possible for the foothills and mountains. The probability for 2 or
more inches of snow is roughly 30-70% for areas along and south of
I-90. An unsettled pattern will cause temperatures to swing back
and forth from the 30s and 40s, to the 20s and 30s at times
through the remainder of the week with precipitation chances and
periods of wind along the western foothills. STP

.AVIATION...

Area of low stratus w/ MVFR ceilings at KBHK will likely linger
near the MT/Dakotas stateline thru much of the night. VFR will
prevail otherwise over the next 24 hours, but there is a low risk
(20% chance) of fog over southeast MT later tonight into Sunday
morning. There is not enough confidence to place BR in a TAF, but
the sites which could be impacted are KSHR & KMLS. Will monitor
through the night. JKL

&&

.PRELIMINARY POINT TEMP/POPS...

    Sun     Mon     Tue     Wed     Thu     Fri     Sat
-----------------------------------------------------------
BIL 001/019 010/033 024/037 016/029 019/036 026/041 031/044
    00/B    00/U    04/O    51/B    02/S    33/O    33/O
LVM 004/027 011/037 025/037 017/034 019/039 025/044 030/045
    00/B    00/B    25/S    41/B    02/S    33/O    34/O
HDN 903/020 004/035 017/037 015/028 012/037 020/042 026/043
    00/B    00/U    16/O    72/S    02/O    44/O    34/O
MLS 906/017 004/027 016/035 010/020 011/035 022/039 024/038
    00/U    00/U    13/O    40/E    01/B    43/O    43/O
4BQ 904/022 008/032 019/037 015/024 014/035 025/040 027/040
    00/U    00/U    02/S    50/E    01/B    33/O    33/O
BHK 910/017 000/025 011/035 005/019 007/034 018/036 020/035
    00/U    00/U    02/S    30/E    01/E    32/S    43/S
SHR 903/026 006/037 017/039 014/029 011/040 020/044 024/045
    00/B    00/U    04/S    71/B    02/S    33/O    33/O

&&

.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...None.
WY...None.

&&

$$
weather.gov/billings